Grayscale Conversion of Histopathological Slide Images as a Preprocessing Step for Image Segmentation

Abstract

This paper presents a method of conversion of color image of histopathological slidesto grayscale as a preprocessing step for image segmentation. The method utilizescharacteristics of these images to reduce the amount of information lost during theconversion. It is a global mapping scheme and the same color does not map to twodifferent grayscale values. Color information is added to the brightness information toreduce information loss and the weights for the added color are dependent on thedistribution of the pixels in a particular image. The method was tested on a large set ofhistopathological slide images and convincing results were obtained some of which hasbeen published in this paper.